1. Technical Field
The present invention relates to an apparatus and method for determining physical characteristics of an array of materials as functions of mechanical perturbations and environmental conditions.
2. Discussion
Combinatorial chemistry generally refers to methods and materials for creating collections of diverse materials or compounds—commonly known as libraries—and to techniques and instruments for evaluating or screening libraries for desirable properties. Combinatorial chemistry has revolutionized the process of drug discovery, and has enabled researchers to rapidly discover and optimize many other useful materials.
Scientists realized that efficient screening techniques were essential for any successful combinatorial research effort. However, since much of the original work in combinatorial chemistry focused on biologically active compounds, early researchers typically employed conventional biological assays as screening methods. Many of these assays were ideally suited for screening combinatorial libraries because they required little or no sample preparation and they could generate useful results using small sample sizes (a mg or less) generally produced in a combinatorial synthesis.
But as researchers began applying combinatorial methods to develop novel non-biological materials, they increasingly found that conventional instruments and methods for characterizing materials were often unsatisfactory for screening. For example, instruments for characterizing physical properties of materials—viscometers, rheometers, dynamic analyzers, and other mechanical property test instruments—are generally unsuitable for screening purposes because they were designed to process one sample at a time. Although the throughput of these serial instruments would likely benefit from automation, many mechanical property test instruments require time-consuming sample preparation, demand more sample than is ordinarily prepared in a high speed research program, and exhibit sluggish environmental control, making such instruments impractical for use as screening tools. Furthermore, the long time scales associated with measuring mechanical properties of polymers, ceramics and other engineered materials often make serial approaches unsuitable as screening methods.
Moreover, competitive pressures are forcing scientists to continually expand their set of screening tools. Many material scientists have embraced combinatorial methodologies because the techniques allow them to develop novel materials in a fraction of the time as conventional discovery methods. This has allowed researchers to tackle a wider range of material design challenges and to consider a broader set of characteristics that ultimately translates into improved material performance. Of course, new design challenges and additional screening criteria mean that laboratories must acquire more screening tools, which if purchased as separate instruments, might offset cost savings associated with combinatorial methods.
Thus, there exists a need for versatile instruments and techniques for screening combinatorial libraries, and especially instruments and methods for measuring physical properties of materials. The present invention, at least in part, satisfies that need.